/* Material Design 3 变量与基础样式 */
        :root {
            /* 主色调 - 可替换 */
            --md-primary: #1E88E5;
            --md-primary-container: #D3E4FD;
            --md-on-primary: #FFFFFF;
            --md-on-primary-container: #001D35;
            
            /* 中性色调 */
            --md-surface: #FEFBFF;
            --md-on-surface: #1B1B1F;
            --md-surface-variant: #E1E2EC;
            --md-on-surface-variant: #44474F;
            --md-outline: #74777F;
            --md-outline-variant: #C4C6D0;
            
            /* 错误色 */
            --md-error: #BA1A1A;
            --md-error-container: #FFDAD6;
            --md-on-error: #FFFFFF;
            --md-on-error-container: #410002;
            
            /* 成功色 */
            --md-success: #006D41;
            
            /* 阴影 */
            --md-elevation-1: 0 1px 2px rgba(0, 0, 0, 0.3), 0 1px 3px 1px rgba(0, 0, 0, 0.15);
            --md-elevation-2: 0 1px 2px rgba(0, 0, 0, 0.3), 0 2px 6px 2px rgba(0, 0, 0, 0.15);
            --md-elevation-3: 0 4px 8px 3px rgba(0, 0, 0, 0.15), 0 1px 3px rgba(0, 0, 0, 0.3);
            
            /* 圆角 */
            --md-radius-small: 4px;
            --md-radius-medium: 8px;
            --md-radius-large: 12px;
            --md-radius-extra-large: 16px;
            --md-radius-full: 50%;
            
            /* 动画 */
            --md-transition-standard: cubic-bezier(0.2, 0, 0, 1);
            --md-transition-emphasized: cubic-bezier(0.2, 0, 0, 1);
        }

        /* 暗色主题 */
        [data-theme="dark"] {
            --md-surface: #1B1B1F;
            --md-on-surface: #E3E2E6;
            --md-surface-variant: #44474F;
            --md-on-surface-variant: #C4C6D0;
            --md-outline: #8E9099;
            --md-outline-variant: #44474F;
            --md-primary-container: #00497D;
            --md-on-primary-container: #D3E4FD;
        }

        * {
            margin: 0;
            padding: 0;
            box-sizing: border-box;
        }

        body {
            font-family: 'Roboto', sans-serif;
            background-color: var(--md-surface);
            color: var(--md-on-surface);
            line-height: 1.5;
            min-height: 100vh;
            display: flex;
            flex-direction: column;
            align-items: center;
            justify-content: center;
            padding: 16px;
            transition: background-color 0.3s var(--md-transition-standard);
        }

        /* 卡片容器 */
        .register-card {
            background-color: var(--md-surface);
            border-radius: var(--md-radius-extra-large);
            box-shadow: var(--md-elevation-3);
            padding: 24px;
            width: 100%;
            max-width: 520px;
            transition: all 0.3s var(--md-transition-standard);
        }

        .register-header {
            margin-bottom: 32px;
            text-align: center;
        }

        .register-title {
            font-size: 28px;
            font-weight: 500;
            margin-bottom: 8px;
        }

        .register-subtitle {
            color: var(--md-on-surface-variant);
            font-size: 14px;
        }

        /* 表单样式 */
        .form-group {
            margin-bottom: 24px;
            position: relative;
        }

        /* 浮动标签输入框 */
        .input-container {
            position: relative;
        }

        .input-field {
            width: 100%;
            padding: 16px;
            padding-top: 24px;
            border: 1px solid var(--md-outline);
            border-radius: var(--md-radius-medium);
            background-color: transparent;
            color: var(--md-on-surface);
            font-size: 16px;
            transition: all 0.2s var(--md-transition-standard);
            outline: none;
        }

        .input-field:focus {
            border-color: var(--md-primary);
            box-shadow: 0 0 0 1px var(--md-primary);
        }

        .input-field.error {
            border-color: var(--md-error);
        }

        .input-label {
            position: absolute;
            top: 18px;
            left: 16px;
            color: var(--md-on-surface-variant);
            font-size: 16px;
            pointer-events: none;
            transition: all 0.2s var(--md-transition-standard);
            transform-origin: left top;
        }

        .input-field:focus + .input-label,
        .input-field:not(:placeholder-shown) + .input-label {
            top: 8px;
            font-size: 12px;
            color: var(--md-primary);
        }

        .input-field.error + .input-label {
            color: var(--md-error);
        }

        /* 密码可见性切换 */
        .password-toggle {
            position: absolute;
            right: 16px;
            top: 50%;
            transform: translateY(-50%);
            background: transparent;
            border: none;
            color: var(--md-on-surface-variant);
            cursor: pointer;
            padding: 4px;
            border-radius: var(--md-radius-small);
            display: flex;
            align-items: center;
            justify-content: center;
            transition: background-color 0.2s var(--md-transition-standard);
        }

        .password-toggle:hover {
            background-color: rgba(0, 0, 0, 0.04);
        }

        [data-theme="dark"] .password-toggle:hover {
            background-color: rgba(255, 255, 255, 0.08);
        }

        /* 密码强度指示器 */
        .password-strength {
            margin-top: 8px;
        }

        .strength-bar {
            height: 4px;
            border-radius: 2px;
            background-color: var(--md-outline-variant);
            overflow: hidden;
            margin-bottom: 4px;
        }

        .strength-fill {
            height: 100%;
            width: 0%;
            transition: all 0.3s var(--md-transition-standard);
        }

        .strength-text {
            font-size: 12px;
            color: var(--md-on-surface-variant);
        }

        .strength-weak .strength-fill {
            background-color: var(--md-error);
            width: 33%;
        }

        .strength-medium .strength-fill {
            background-color: #FF9800;
            width: 66%;
        }

        .strength-strong .strength-fill {
            background-color: var(--md-success);
            width: 100%;
        }

        /* 复选框 */
        .checkbox-group {
            display: flex;
            align-items: flex-start;
            gap: 12px;
            margin-bottom: 24px;
        }

        .checkbox-container {
            position: relative;
            display: inline-block;
            width: 18px;
            height: 18px;
            flex-shrink: 0;
            margin-top: 2px;
        }

        .checkbox-input {
            opacity: 0;
            position: absolute;
            width: 100%;
            height: 100%;
            cursor: pointer;
        }

        .checkbox-box {
            width: 18px;
            height: 18px;
            border: 2px solid var(--md-outline);
            border-radius: 2px;
            display: flex;
            align-items: center;
            justify-content: center;
            transition: all 0.2s var(--md-transition-standard);
        }

        .checkbox-input:checked + .checkbox-box {
            background-color: var(--md-primary);
            border-color: var(--md-primary);
        }

        .checkbox-input:checked + .checkbox-box::after {
            content: '';
            width: 6px;
            height: 10px;
            border: solid white;
            border-width: 0 2px 2px 0;
            transform: rotate(45deg);
            margin-top: -2px;
        }

        .checkbox-label {
            font-size: 14px;
            color: var(--md-on-surface);
        }

        .checkbox-link {
            color: var(--md-primary);
            text-decoration: none;
        }

        .checkbox-link:hover {
            text-decoration: underline;
        }

        /* 提交按钮 */
        .submit-button {
            width: 100%;
            background-color: var(--md-primary);
            color: var(--md-on-primary);
            border: none;
            border-radius: var(--md-radius-large);
            padding: 16px;
            font-size: 16px;
            font-weight: 500;
            cursor: pointer;
            transition: all 0.2s var(--md-transition-standard);
            position: relative;
            overflow: hidden;
            text-transform: uppercase;
            letter-spacing: 0.5px;
            margin-bottom: 16px;
        }

        .submit-button:hover:not(:disabled) {
            background-color: #0d7cd6;
            box-shadow: var(--md-elevation-1);
        }

        .submit-button:disabled {
            background-color: var(--md-outline-variant);
            color: var(--md-on-surface-variant);
            cursor: not-allowed;
        }

        /* 登录链接 */
        .login-link {
            text-align: center;
            margin-top: 16px;
        }

        .login-link a {
            color: var(--md-primary);
            text-decoration: none;
            font-size: 14px;
            transition: color 0.2s var(--md-transition-standard);
        }

        .login-link a:hover {
            text-decoration: underline;
        }

        /* Ripple 效果 */
        .ripple {
            position: absolute;
            border-radius: 50%;
            background-color: rgba(255, 255, 255, 0.7);
            transform: scale(0);
            animation: ripple 0.6s linear;
            pointer-events: none;
        }

        @keyframes ripple {
            to {
                transform: scale(4);
                opacity: 0;
            }
        }

        /* 加载状态 */
        .submit-button.loading {
            pointer-events: none;
        }

        .loading-spinner {
            display: inline-block;
            width: 20px;
            height: 20px;
            border: 2px solid transparent;
            border-top: 2px solid var(--md-on-primary);
            border-radius: 50%;
            animation: spin 1s linear infinite;
            margin-right: 8px;
        }

        @keyframes spin {
            0% { transform: rotate(0deg); }
            100% { transform: rotate(360deg); }
        }

        /* 错误提示 */
        .error-text {
            color: var(--md-error);
            font-size: 12px;
            margin-top: 4px;
            display: flex;
            align-items: center;
            gap: 4px;
        }

        /* Toast 通知 */
        #toast {
            position: fixed;
            top: 50%;
            left: 50%;
            transform: translate(-50%, -50%) scale(0.8);
            background-color: rgba(0, 0, 0, 0.8);
            color: white;
            padding: 16px 24px;
            border-radius: var(--md-radius-large);
            z-index: 1000;
            opacity: 0;
            visibility: hidden;
            transition: all 0.3s var(--md-transition-standard);
            display: flex;
            align-items: center;
            gap: 12px;
            min-width: 200px;
            text-align: center;
        }

        #toast.show {
            opacity: 1;
            visibility: visible;
            transform: translate(-50%, -50%) scale(1);
        }

        .toast-icon {
            width: 20px;
            height: 20px;
            border-radius: 50%;
            display: flex;
            align-items: center;
            justify-content: center;
            font-size: 14px;
        }

        .toast-icon.success {
            background-color: var(--md-success);
        }

        .toast-icon.error {
            background-color: var(--md-error);
        }

        .toast-text {
            flex: 1;
            font-weight: 500;
        }

        /* 响应式设计 */
        @media (max-width: 600px) {
            .register-card {
                padding: 16px;
            }
        }
        
        
     
     
     
        
        /* 品牌图片区域样式 */
.brand-section {
    display: flex;
    flex-direction: column;
    align-items: center;
    margin-bottom: 2rem;
    padding: 1rem;
}

.brand-logo {
    margin-bottom: 0.5rem;
}

.brand-image {
    width: 80px;
    height: 80px;
    object-fit: contain;
}

.brand-name {
    font-size: 1.5rem;
    font-weight: 500;
    color: #7B1FA2;
    letter-spacing: 0.5px;
}